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struts2 OGNL的用法介绍(二)

2014-11-24 10:11:48 · 作者: · 浏览: 5
标签: struts2 OGNL 用法 介绍
n person1 = new Person(); person1.setName("zhangsan"); Person person2 = new Person(); person2.setName("lisi"); Person person3 = new Person(); person3.setName("wangwu"); /* person4不放入到上下文环境中*/ Person person4 = new Person(); person4.setName("zhaoliu"); /* 将person1、person2、person3添加到环境中（上下文中）*/ context.put("person1", person1); context.put("person2", person2); context.put("person3", person3); try { /* 获取根对象的"name"属性值*/ Object value = Ognl.getValue("name", context, person2); System.out.println("ognl expression \"name\" eva luation is : " + value); /* 获取根对象的"name"属性值*/ Object value2 = Ognl.getValue("#person2.name", context, person2); System.out.println("ognl expression \"#person2.name\" eva luation is : " + value2); /* 获取person1对象的"name"属性值*/ Object value3 = Ognl.getValue("#person1.name", context, person2); System.out.println("ognl expression \"#person1.name\" eva luation is : " + value3); /* 将person4指定为root对象，获取person4对象的"name"属性，注意person4对象不在上下文中*/ Object value4 = Ognl.getValue("name", context, person4); System.out.println("ognl expression \"name\" eva luation is : " + value4); /* 将person4指定为root对象，获取person4对象的"name"属性，注意person4对象不在上下文中*/ Object value5 = Ognl.getValue("#person4.name", context, person4); System.out.println("ognl expression \"person4.name\" eva luation is : " + value5); /* 获取person4对象的"name"属性，注意person4对象不在上下文中*/ // Object value6 = Ognl.getValue("#person4.name", context, person2); // System.out.println("ognl expression \"#person4.name\" eva luation is : " + value6); }

2）使用OGNL调用方法 
public static void main(String[] args)  
    {  
        /* OGNL提供的一个上下文类，它实现了Map接口*/  
        OgnlContext context = new OgnlContext();  
  
        People people1 = new People();  
        people1.setName("zhangsan");  
  
        People people2 = new People();  
        people2.setName("lisi");  
  
        People people3 = new People();  
        people3.setName("wangwu");  
  
        context.put("people1", people1);  
        context.put("people2", people2);  
        context.put("people3", people3);  
         
        context.setRoot(people1);  
  
        try  
        {  
            /* 调用 成员方法*/  
            Object value = Ognl.getValue("name.length()", context, context.getRoot());  
            System.out.println("people1 name length is :" + value);  
             
            Object upperCase = Ognl.getValue("#people2.name.toUpperCase()", context, context.getRoot());  
            System.out.println("people2 name upperCase is :" + upperCase);  
  
            Object invokeWithArgs = Ognl.getValue("name.charAt(5)", context, context.getRoot());  
            System.out.println("people1 name.charAt(5) is :" + invokeWithArgs);  
  
            /* 调用静态方法*/  
            Object min = Ognl.getValue("@java.lang.Math@min(4,10)", context, context.getRoot());  
            System.out.println("min(4,10) is :" + min);  
  
            /* 调用静态变量*/  
            Object e = Ognl.getValue("@java.lang.Math@E", context, context.getRoot());  
            System.out.println("E is :" + e);  
        }

3）使用OGNL操作集合 
public static void main(String[] args) throws Exception  
    {  
        OgnlContext context = new OgnlContext();  
         
        Classroom classroom = new Classroom();  
        classroom.getStudents().add("zhangsan");  
        classroom.getStudents().add("lisi");  
        classroom.getStudents().add("wangwu");  
        classroom.getStudents().add("zhaoliu");  
        classroom.getStudents().add("qianqi");  
         
        Student student = new Student();  
        student.getContactWay